Comparing two correlated C indices with right-censored survival outcome: a one-shot nonparametric approach.
Comparing two correlated C indices with right-censored survival outcome: a one-shot nonparametric approach.
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DOI：
10.1002/sim.6370
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发表时间：
2015-02-20
影响因子：
2
通讯作者：
Gallas, Brandon D.
中科院分区：
文献类型：
--
作者：
Kang, Le;Chen, Weijie;Petrick, Nicholas A.;Gallas, Brandon D.
当临床结果(TRUE)为二元时，受试者工作特征(ROC)曲线下的面积(AUC)通常被用作评估生物标志物诊断能力的综合指标。当临床结果是右审查生存时间时，Harrell提出了C指数，作为AUC的延伸，作为预测性生物标记物和右审查生存结果之间的一致性的度量。在这项工作中，我们研究了两个诊断或预测系统的统计比较方法，它们可以是两个生物标记物或两个固定算法，就其C指数而言。我们采用了一个基于U-统计量的渐近正态C估计，并发展了一种非参数分析方法来估计C估计的方差和两个C估计的协方差。然后构建z-Score检验来比较两个C指数。我们通过仿真研究从I类错误率和功率方面验证了我们的单次非参数方法。我们还比较了我们的一次采样法与重采样法，包括折叠法和自举法。仿真结果表明，该方法提供了几乎无偏的方差估计，并且具有令人满意的第I类差错控制和功率。最后，我们用Framingham心脏研究中的一个例子来说明所提出的方法的使用。
The area under the receiver operating characteristic (ROC) curve (AUC) is often used as a summary index of the diagnostic ability in evaluating biomarkers when the clinical outcome (truth) is binary. When the clinical outcome is right-censored survival time, the C index, motivated as an extension of AUC, has been proposed by Harrell as a measure of concordance between a predictive biomarker and the right-censored survival outcome. In this work, we investigate methods for statistical comparison of two diagnostic or predictive systems, of which they could either be two biomarkers or two fixed algorithms, in terms of their C indices. We adopt a U-statistics based C estimator that is asymptotically normal and develop a nonparametric analytical approach to estimate the variance of the C estimator and the covariance of two C estimators. A z-score test is then constructed to compare the two C indices. We validate our one-shot nonparametric method via simulation studies in terms of the type I error rate and power. We also compare our one-shot method with resampling methods including the jackknife and the bootstrap. Simulation results show that the proposed one-shot method provides almost unbiased variance estimations and has satisfactory type I error control and power. Finally, we illustrate the use of the proposed method with an example from the Framingham Heart Study.
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影响因子：
4
作者：
Chen W;Samuelson FW;Gallas BD;Kang L;Sahiner B;Petrick N
通讯作者：
Petrick N
影响因子：
2
作者：
HARRELL, FE;LEE, KL;ROSATI, RA
通讯作者：
ROSATI, RA
影响因子：
1.8
作者：
DORFMAN, DD;ALF, E
通讯作者：
ALF, E
DOI：
10.1016/0735-1097(93)90455-a
发表时间：
1993-10-01
影响因子：
24
作者：
HO, KKL;PINSKY, JL;LEVY, D
通讯作者：
LEVY, D
影响因子：
2
作者：
HENDERSON, R
通讯作者：
HENDERSON, R